Recoil-less hammer head construction



March 6, 1956 s. M. KENERSON RECOIL-LESS HAMMER HEAD CONSTRUCTION FiledDec. 23, 1953 F/Gl.

, IN VEN TOR.. 57774645) M AE/VEPSOM g fiice 2,737,216 Fatentecl Mar. 6,1956 RECOIL-LESS HAMMER HEAD CflNSTRUCTIGN Stanley M. Kenerson,Springfield, Mass, assignor to Metacraft Alloy Corporation, WestSpringfield, Mass, a corporation of Massachusetts Application December23, 1953, Serial No. diltidtfitl 2 Claims. (Cl. 145-29) This inventionrelates to hammer constructions of the type in which the head of ahammer is Weighted with a shifting mass of material in a chamber of thehead so that when a blow is struck the inertia of the material in thechamber moving in the direction of the blow will counteract the tendencyof the hammer head to recoil or rebound.

This type of hammer and its advantages are well known. The head of thehammer is usually provided with a chamber extending longitudinallythereof and in the chamber is located a quantity of heavy comminutedmaterial as fine lead shot. Commonly the chamber is provided in thestriking end of the head by the endwise cutting of a cylindrical bore,lead shot being deposited in the bore and a plug sealed therein to formthe closed chamber. Every time a blow is struck the impact of theshifting mass of lead shot is thus received directly on the sealed plug.The force of the mass in dampening the rebound and eliminating recoil istransmitted to the plug in such a way as to cause the plug to workloose, become unseated, and render the hammer useless for its intendedpurpose.

An object of the present invention is to provide a construction in whichthe striking element of this type of hammer is separated from directimpact by the movable weight and thus the useful life of the hammergreatly increased.

The invention resides in the particular arrangement, construction, andrelationship of the various elements of the hammer head as disclosed inthe accompanying specification in which the above and other objects ofthe invention will be apparent.

In the drawings,

Fig. l is a side elevational view of a hammer embodying the inventionand partially in section to show details of construction;

Fig. 2 is an end elevation of the head as viewed from the right of Fig.l;

Fig. 3 is a fragmentary sectional view of one end of the recessed bodymember showing the assembly step of inserting a disc to close off therecess and form a sealed chamber in said member; and

Fig. 4 is a sectional view on line 4-4 of Fig. l.

The hammer head as shown by the drawings comprises a body member 1 andcap portions 2 fitted at either end of the body member. A transversebore 3 is located centrally of the body 1 to receive a handle 4crosswise of the head. The bore 3 is preferably tapered outwardly towardeach end from a central cylindrical section provided with knurled ridgesas at 5. The handle (Fig. 2) may be anchored to the head by driving thesame into the bore 4 and wedging it as with a wooden wedge piece 6 and asteel wedge 7 set crosswise of the wood wedge. Thus the handle issecurely attached against removal.

The body member 1 is preferably of metal, and is cupshaped at either endto form recesses 8. The outer end portion 9 of the wall of the cuppedbody member is of reduced diameter and provides a shouldered peripheralledge at 10 for the seating of the outer rim 11 of the telescopicallyfitted cupped shaped striker cap 2. The cap 2 is preferably of hardplastic material embracing the end of the body member 1 with its innerbase wall at 13 of the cup in spaced relation to the rim of the Wall 9.The cap 2 serves as the striker element of the hammer and is suitablypress fitted and cemented to the body member.

The recess 8 is partially filled with a movable weighted material as themass at 14 of fine lead shot, preferably of the type known as dust shot.At its outer rim the recess S is provided with a closure disc 15. Thedisc 15 is seated on the edge of the wall 9 being secured into positionby the shouldered lip 16. As in Fig. 3 which illustrates the step ofassembling the disc 15 into place, the edge of the disc rests on theshouldered rim of the wall 9 being located by the lip 16 which is thenturned over onto the upper edge of the disc as by peening the metal ofthe lip to anchor the closure disc into place. The disc thus forms aclosed chamber for containing the charge of dust shot and for sealingthe shot from direct contact with the striker cap 2.

As will be noted the force of the moving mass 14 in striking a blow withthe hammer will be indirectly transmitted to the striker cap 2 throughthe telescopically attached walls thereof abutting at the shoulder 10.The mass or shot will move directly against the closure disc which iseffectively sealed by the lip 16 against removal. Thus the oppositelyacting force of the movable weight in counteracting the recoil of thehead will have no tendency to tear at the cap member and jar or pry thesame from its anchorage on the body member.

What is claimed is:

l. Ina hammer, a hammer head construction comprising a body memberhaving means for attachment of a handle thereto and a cap member forstriking a blow with said hammer, said cap and body members havingintegrally formed opposed cup-shaped recesses with said body memberbeing telescopically received by said cap and provided with an externalwall of reduced cross section forming a shoulder against which thecupped rim of said cap is seated, the cup of said body member having aninternally shouldered rim forming a lip with a closure disc seated onsaid rim and engaged by said lip to anchor said disc against removaltherefrom, a quantity of weighted material partially filling the chamberformed by the disc and recess of said body member, the bottom of saidcupped recess of the cap member being in spaced relation to said discand said disc receiving the direct impact of said weighted material inshifting the material towards said cap when a blow is struck by thehammer.

2. In a hammer, a hammer head construction comprising a cylindricalmetallic body portion having a transverse bore centrally thereof forreceiving a handle crosswise of the body portion, said body portionhaving oppositely directed outwardly facing cupped recesses at the endsthereof with the outer wall section at said ends being of reduceddiameter and providing a shouldered seat spaced from the ends, a strikercap of cupped formation having an outer wall integral therewith ofsubstantially the diameter of said body portion and being telescopicallyreceived at each end of the body and anchored against said shoulders,said cupped recess at each end of the body portion having a shoulderedrim formed with an outer peripheral lip, a disc seated on said shoulderclosing each recess with said lip being turned against said disc toanchor the same in the mouth of said recess, said discs 3 4 and theadjacent walls of said caps being in spaced rela- 608,349 Sterne Aug. 2,1898 tion with the chamber formed by said cupped recess of 637,158Prouty Nov. 14, 1899 a body portion and a closure disc being partiallyfilled 2,451,217 Heinrich Oct. 12, 1948 with lead shot material.2,518,059 Pemmerl Aug. 8, 1950 5 2,566,517 Dicks Sept. 4, 1951References (Jited in the file of this patent 2, 04,914 Kahlen July 291952 UNITED STATES PATENTS 460,115 Colton Sept. 29, 1891

